The invention relates to a flexible brush head for a toothbrush.
The object of the present invention is to provide a flexible, adaptable brush head which allows better cleaning of the teeth as a whole.
The design of the brush head according to the invention makes it very flexible. It has a bristle carrier which is made of a first, hard but elastic plastic and is divided up into at least two segments, which are located one behind the other along the longitudinal axis of the brush head, by at least one recess, which passes through the bristle carrier, in the form of a tunnel, transversely with respect to the longitudinal axis of the brush head.
The segments of the bristle carrier, and preferably also the tunnel, extend over the entire width of the brush head, the tunnel preferably being filled with a second, rubber-elastic plastic, which is much softer than the first plastic of the bristle carrier, with the result that there is no risk of the tunnel being contaminated. The design described allows the individual segments of the bristle carrier to be deflected with respect to one another, which results in the brush head being flexible. Since the brush head can bend about an axis running transversely with respect to the longitudinal axis of the brush head, adaptation both to the outsides and the insides of the teeth is possible, this allowing more careful cleaning of the teeth, of the spaces between the teeth and of the gum line. Slight turning of the individual segments of the bristle carrier with respect to one another, that is to say slight torsion of the brush head, is also possible, this further improving adaptation of the brushing surface, which is produced by the bristles or bristle clusters, to the shapes of the individual teeth and of the teeth as a whole, and thus further improving the cleaning operation. If the brush head is subjected to pronounced or excessive pressure, it bends to a correspondingly more pronounced extent and thus compensates for some of the pressure. This means that gentler and more careful cleaning is possible.
If the brush head has more than just two segments and, accordingly, more than one tunnel, then the flexibility of the brush head increases and the effects outlined are enhanced.
The flexibility of the brush head can be increased further if the regions of the bristle carrier which bound the tunnels on the bristle-carrying side of the bristle carrier and on the side which is located opposite the bristle-carrying side of the bristle carrier are configured such that they can be expanded and/or compressed in the longitudinal direction of the brush head. In order to achieve greater stability of the brush head, it is expedient for these regions to be configured in the expansible form described just on one side in each case, and advantageously on the bristle-carrying side. A configuration in the form of a web which is folded in the manner of an accordion is particularly suitable. A bristle-carrier region which is configured in expansible form with or without folding and bounds the tunnel of said sides yields elastically to its limit of expansion and thus acts as a bending-limiting means. When the limit of expansion is reached, further deflection or turning of the segments with respect to one another is only possible by force being applied. Automatic return of the segments into their original position is effected predominantly by the elastic restoring action of said bristle-carrier regions which bound the tunnels, and also by the second, soft, elastic plastic, with which the tunnel is filled and which is joined firmly to the first, hard, elastic plastic of the bristle carrier.
For producing a brush head of the type described, it is advantageous if, for the case where more than one tunnel is provided in the brush head, the tunnels are connected to one another, since it is easier in this way for them to be filled with the second, soft, rubber-elastic plastic. If the intention is to produce entire toothbrushes, then it is advantageous to form the brush head integrally on a brush handle or a plug-on part and to produce said handle or plug-on part likewise from the first, hard but elastic plastic.
Further advantageous embodiments of the brush head and toothbrushes with brush heads according to the invention are seen in the several drawing figures and are described herein.